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The documentation on this page is for a legacy release of Dyalog. For documentation for the current release, see Documentation for Dyalog v19.0.
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      Documentation for Dyalog v12.1

      Legacy

      Unsupported

      The documentation on this page is for Dyalog v12.1 and components shipped with that release. For documentation for other Dyalog versions, see All Versions of Dyalog.

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      Language Help

      Dyalog v12.1 Help (online)

      Dyalog v12.1 Help (offline)

      Release Notes

      Dyalog v12.1 Release Notes

      Dyalog v12.0 Release Notes

      Dyalog v11.0 Release Notes

      Core Product Manuals

      Language Reference

      Object Reference

      User Guide

      DotNet Interface Guide

      Interface Guide

      Tools

      Causeway Pro

      Conga v2.0 User Guide

      Guide to the Code Libraries

      New Leaf

      Rain Pro

      SALT - the Simple APL Library Tookit

      SQAPL Release Notes Version 6.0

      SQAPL Release Notes Version 5.0

      Workspace Transfer Guide

      User Commands

      Tutorials

      Introduction to Object Oriented Programming for APL Programmers

      Object Oriented Programming for Impatient APL'ers

      Internet Resources

      Dyalog Forums

      Frequently Asked Questions

      APL Wiki

      Vector - The journal of the British APL Association

      All Versions of Dyalog

      This section contains links to the documentation for all versions of Dyalog since version 12.0 (both current and legacy documentation).

      Latest Version of Dyalog

      The current version of Dyalog is v19.0.
      • Documentation Centre: v19.0
      • Online documentation: v19.0

      Previous Versions of Dyalog

      Supported versions: Unsupported versions:

      Release Notes (PDFs)

      This section contains links to the Release Notes (PDFs) for all versions of Dyalog since version 12.0.

      v19.0, v18.2, v18.0, v17.1, v17.0, v16.0, v15.0, v14.1, v14.0, v13.2, v13.1, v13.0, v12.1, v12.0

      Retired Documentation

      The Retired Documentation page lists documents that have been deprecated.

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      Copyright © 2004 – 2025 Dyalog Ltd.

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      Get Support

      Technical advice and assistance on all aspects of Dyalog usage is available by e-mail (support@dyalog.com) and/or telephone (+44 1256 830030 – limited to U.K. office hours). Limited advice on design and coding is available, but is not intended to replace the use of the printed and on-line documentation. Except when reporting an issue with the software, users are encouraged to seek advice from the user community via the Dyalog Forum (reading the content of the forums does not require membership).

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